using System;
using System.Collections.Generic;
using System.Linq;
using Neo.Afx.ComponentModel;
using Neo.Afx.Services.Audits.Entities;
using System.Reflection;

namespace Neo.Afx.Services.Audits
{
    /// <summary>
    /// Audit database context container
    /// </summary>
    public class AuditsDatabase : Database<AuditContext>
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="AuditsDatabase"/> class.
        /// </summary>
        public AuditsDatabase()
            : base(new AuditContext())
        {
            Context.Configuration.AutoDetectChangesEnabled = false;
            Context.Configuration.ValidateOnSaveEnabled = false;
        }

        #region GetAudits

        /// <summary>
        /// Gets the audits.
        /// </summary>
        /// <param name="entityID">The entity ID.</param>
        /// <param name="itemID">The item ID.</param>
        /// <param name="sourceID">The source ID.</param>
        /// <param name="actionID">The action ID.</param>
        /// <param name="order">The order.</param>
        /// <returns></returns>
        public IEnumerable<Vw_Audits> GetAudits(int entityID, long itemID, short? sourceID, short? actionID, string order)
        {
            if (String.IsNullOrEmpty(order) || order.ToLower() != "asc" || order.ToLower() != "desc")
            {
                order = "asc";
            }

            var results = (from q in Context.Vw_Audits
                           where q.EntityID == entityID && q.ItemID == itemID
                           select q).ToList();

            if (sourceID.HasValue && sourceID.Value != -1)
            {
                results = results.Where(a => a.SourceID == sourceID.Value).ToList();
            }

            if (actionID.HasValue && actionID.Value != -1)
            {
                results = results.Where(a => a.ActionID == actionID.Value).ToList();
            }

            return order == "asc" ? results.OrderBy(a => a.AuditDate) : results.OrderByDescending(a => a.AuditDate);
        }

        #endregion

        #region WriteEntry(int userID, string source, string action, string description, bool isCritical, bool isException, int entityID, long? itemID)
        /// <summary>
        /// Writes an entry to the audit log
        /// </summary>        
        public void WriteEntry(long userID, string source, string action, string description, bool isCritical, bool isException, int entityID, long? itemID)
        {
            Context.Pr_WriteEntryByID(userID, source, action, description, isCritical, isException, entityID, itemID);
        }
        #endregion

        #region WriteEntries
        /// <summary>
        /// Writes mutliple entries to the audit trail
        /// </summary>
        /// <param name="sourceID"></param>
        /// <param name="actionID"></param>
        /// <param name="changes"></param>
        /// <param name="entityID"></param>
        /// <param name="itemID"></param>
        /// <param name="createdByID"></param>
        public void WriteEntries(short sourceID, short actionID, List<string> changes, int entityID, long itemID, long createdByID)
        {
            foreach (var change in changes)
            {
                Context.History.Add(new History()
                {
                    ActionID = actionID,
                    CreatedByID = createdByID,
                    CreatedDate = DateTime.Now,
                    Description = change,
                    EntityID = entityID,
                    ItemID = itemID,
                    SourceID = sourceID
                });
            }
            Context.SaveChanges();
        }
        #endregion

        #region GetEntityDifferences
        /// <summary>
        /// Comparexs two objects and returns the differences
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="obj1"></param>
        /// <param name="obj2"></param>
        /// <param name="idPropertyName"></param>
        /// <returns></returns>
        public IEnumerable<string> GetEntityDifferences<T>(T obj1, T obj2, string idPropertyName)
        {
            var type = obj1.GetType().ToString();
            var idValue = typeof(T).GetProperty(idPropertyName).GetValue(obj1, null);
            PropertyInfo[] properties = typeof(T).GetProperties();
            List<string> changes = new List<string>();

            if (type.Contains("."))
            {
                type = type.Substring(type.LastIndexOf(".") + 1);
            }

            if (idValue == null)
            {
                idValue = "-1";
            }

            foreach (PropertyInfo pi in properties)
            {
                object value1 = typeof(T).GetProperty(pi.Name).GetValue(obj1, null);
                object value2 = typeof(T).GetProperty(pi.Name).GetValue(obj2, null);

                if (pi.PropertyType == typeof(string) || pi.PropertyType.IsValueType)
                {
                    if (value1 != value2 && (value1 == null || !value1.Equals(value2)))
                    {
                        if (value1 == null)
                        {
                            value1 = "nothing";
                        }

                        if (value2 == null)
                        {
                            value2 = "nothing";
                        }

                        changes.Add(string.Format("{0}, ID {1}, Property {2} changed from {3} to {4}", type, idValue, pi.Name, value1, value2));
                    }
                }
            }

            return changes;
        }
        #endregion

    }
}